Did anybody get arrested for spreading tacks on the road in this years "Tour De France " ?

No, for the simple reason that the race is over hundreds of kilometres and you can't watch every metre of it. The sick person who did that probably did it either when there was noone around or right in the middle of an excited crowd looking at the coming bikers and not taking notice of a simple throwing gesture in the middle of waving arms and cheering people.

I found this to be a most interesting question. I will immediately look into it myself. I am thinking
of the Monica Seles tennis incident in Germany- stabbed by a spectator and basically finished off her wonderful career. The person that did this terrible thing - got a very minor penalty and Ms Seles is still upset by the court's decision.

I've linked some stories below. The second one has an on-line poll and 100% of the responders (no idea how many, perhaps I was the only one) said the perps should go to jail.

I couldn't find a story about an arrest. Maybe the French cops are waiting until a rider gets seriously injured before they actually care about the matter. As it was, one rider was hurt and had to leave the race.

Hypodermic needles more appropriate i guess?

If Romney was in it, he would be spreading taxes. I would.